Finding the maximum clique is a NP-hard problem [1]}. We ran the maximum clique algorithm [2]}, [3]}, [4]}, [5]} as implemented in NetworkX [6]} on all three social network graphs. However, when running on \(G_{1}\) , the program ran for several days and then crashed due to insufficient memory in the computer. A similar problem occurred, when using the maximal clique algorithm [2]}, [3]} implemented in NetworkX.
